Core B - 'The Equipment Core'. The 'Equipment Core' supports the major equipment used to characterized the dynamical nature of the protein systems of the various projects of the Program Project. Two spectroscopic approaches are supported: 1. Temperature-jump relaxation spectroscopy. Three instruments are employed to cover the entire time range from 10 ps to minutes (or longer) in three overlapping time domains. (a) 10 ps - 10 ns. The T-jump is performed by heating water by laser irradiation, and the resolution of the instrument is set by the thermalization time of the absorbed energy. This picosecond instrument is located at Los Alamos. Both IR and UV/Vis absorbance and emission can be performed as probes of protein structure. (b) 15 ns-10 ms. The T-jump is achieved by heating water by laser irradiation. Three separate spectrometers will be employed. Two instruments are located at Albert Einstein and perform UV/Vis absorbance and/or fluorescence. IR transient studies will be performed at Los Alamos. (c) 1 ms - minutes (or longer). This instrument will be purchased and based at Einstein. The T-jump is achieved by mixing two solutions at different temperatures and holding the mixed solution at a final temp. Optical (UV/Vis) emission and or absorbance and IR absorbance spectroscopies are employed as structural probes. 2. A static isotope editing IR difference spectrometer located at Albert Einstein. In general, static thermal measurements precede T-jump kinetic studies. These calibrate the expected signal size to be observed in the kinetic work and also sets the magnitude of signal at infinite time in the kinetics experiments.